1. Field of the Invention
The present invention is generally directed to material handling devices in the semiconductor manufacturing industry, and, more particularly, to a device for handling devices, such as reticles, in a semiconductor manufacturing environment.
2. Description of the Related Art
The manufacture of integrated circuit devices, e.g., memory devices, logic devices, etc., is a very complex activity that requires very precise tools and processes. Manufacturing such integrated circuit products may involve hundreds of complex process operations that involve well-known deposition, etching, photolithography and planarization techniques and equipment. Manufacturers of integrated circuit devices go to great lengths in attempting to insure that the manufacturing environment for such integrated circuit devices is extremely clean. If the integrated circuit devices have sufficient particle contamination, the operational capability of the integrated circuit device may be reduced or, in some cases, destroyed.
The manufacture of integrated circuits involves many processes. One process that is universally employed in manufacturing such devices is photolithography. In general, photo-lithography involves forming a layer of photoresist material above a semiconducting substrate and, thereafter, irradiating the photoresist material with light that is projected through a reticle. Through this process, the pattern on the reticle is transferred to the layer of photoresist material. Ultimately, the exposed layer of photoresist will be developed to thereby define a photoresist mask layer. The mask layer may be used to pattern an underlying layer of material using etching processes that are well known to those skilled in the art.
Reticles used in manufacturing modern integrated circuit devices must exhibit a very high degree of precision and are very expensive to manufacture. For example, a typical reticle employed in manufacturing memory devices may cost approximately $60,000-$90,000 depending upon the complexity of the image formed on the reticle.
Unfortunately, it is frequently necessary for personnel to handle or move such reticles for a variety of reasons, e.g., a new product is being processed. The reticles are typically made of glass and may have a generally rectangular or square shape. A reticle may have a thickness of approximately 0.25-0.325 inches. Thus, great care must be exercised when handling such reticles as they may break or crack if dropped or otherwise subjected to undesirable impact loads or stresses. It is also extremely important that such reticles be free of particle contaminants as such particles may scratch the surface of the reticle and/or adversely impact the pattern transferred to the underlying layer of photoresist during the photolithography process.
FIG. 1 depicts an illustrative prior art reticle pick 10 that is employed in handling a reticle 12. The pick 10 generally comprises a body 14, a trigger 16, a spring 18, a pivot point 20, and a plurality of grippers 22. In operation, the trigger 16 is depressed which compresses the spring 18. The force generated by the compressed spring 18 tends to force the upper gripper 22A in the direction indicated by the arrow 24. Thus, the compression of the spring 18 provides the force to clamp the reticle 12 within the grippers 22.
There are several problems associated with the use of the prior art pick 10 depicted in FIG. 1. For example, the compression/relaxation cycle experienced by the spring 18 during operation can lead to the generation of undesirable particles that may contaminate the reticle 12 or other aspects of the semiconductor manufacturing environment. Additionally, over time, the spring 18 may tend to rust, thereby generating additional particles. Typically, such a spring-type pick 10 is subjected to relatively frequent maintenance procedures, such as frequent removal and cleaning, in an effort to reduce the contaminants resulting from the spring 18. Such maintenance efforts are time-consuming and may not effectively prevent the problems caused by such spring-type picks 10.
The present invention is directed to a device and various methods that may solve, or at least reduce, some or all of the aforementioned problems.
While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims.